Functional Units; I/O Adapter Control; Keyboard - IBM 5251 Series Maintenance Information Manual

Functional Units
I/O ADAPTER CONTROL
The I/O adapter control is composed of a group of
registers that control the interface and address functions
of the I/O devices. These registers are controlled by the
MPU (microprocessing unit) and are loaded with data
from the I/O devices. The data is moved to read / write
storage by the MPU.
Status Switch
01--------
Planar
4-4
1-;"'-'
---------~ ~
-
- - - - - l
Keyboard
I
I ·
I
Command
I
Magnetic
Magnetic
Stripe
Stripe
Reader
Reader
Adapter
Light
Light
Pen
Pen
Adapter
To
Controller - _ ......... ,
To Next
Terminal
___ c)-
Cable Thru
Feature
or Address
4
Register
I/O Data
Register
Cable
Adapter
2
[Q]
T
Address Switches
I
I
I
I
Read-Only'
Storage
10
' - 1 - - - - - 4
Microprocessing
I
Unit
I
J
Read/Write
Storage
Display
Adapter
Q-
0 Line Check
o~
Line Sync
e
0
Internal Check
e-
0
Storage Check
. A
0
Ready
Bnghtness
_
Control
Contrast Control
______ :::J
Power
Supply
Horizontal, Vertical,
and Video Signals
Power
Switch